Instability of two-dimensional heterotic stringy black holes

TL;DR

This paper investigates the stability of two-dimensional heterotic stringy black holes, finding that non-extremal black holes are unstable while extremal ones are stable, through solving the eigenvalue problem in general relativity.

Contribution

It provides the first detailed eigenvalue analysis of charged black holes in two-dimensional heterotic string theory, identifying stability conditions.

Findings

Non-extremal black holes exhibit unstable growing modes.

Extremal black holes are stable.

Eigenvalue problem solutions determine stability conditions.

Abstract

We solve the eigenvalue problem of general relativity for the case of charged black holes in two-dimensional heterotic string theory, derived by McGuigan et al. For the case of $m^{2}>q^{2}$, we find a physically acceptable time-dependent growing mode; thus the black hole is unstable. The extremal case $m^{2}=q^{2}$ is stable.